Hurricane Maria, a Category 1 storm, will hit the Leeward Islands on the edge of the Caribbean Sea Monday night, forecasters say, threatening areas that are still coping with the devastation brought by Hurricane Irma two weeks ago. Predictions call for it to pass straight over Puerto Rico on Wednesday.

“Significant strengthening is forecast during the next 48 hours, and Maria is expected to become a dangerous major hurricane before it moves through the Leeward Islands,” the National Hurricane Center says.

Maria’s maximum winds are currently at 90 mph; they could reach 140 mph over the next 48 hours, the center said Monday.

A hurricane warning — meaning hurricane conditions are expected to strike — has been issued for the islands of Guadeloupe, Dominica, St. Kitts, Nevis, and Montserrat, and Martinique. A tropical storm warning is in effect for Antigua and Barbuda.

Puerto Rico and the neighboring the British and U.S. Virgin Islands are under a hurricane watch, meaning hurricane conditions are possible within 48 hours.

The eye of Hurricane Maria is forecast to pass over the center of Puerto Rico on Wednesday. National Hurricane Center

An Air Force Reserve Unit Hurricane Hunter aircraft is scheduled to fly a route in and around Maria this morning to investigate the storm’s development, the hurricane center said.

Unlike Irma, which took a relatively flat westward angle as it raked Barbuda, St. Martin, Cuba and other islands and stormed toward the Florida Keys, Maria is expected to take a sharper northwest tack, passing east of the Turks and Caicos as it heads toward the Bahamas.

Maria puts many of those same areas at risk — including the Virgin Islands, parts of which were hit by Irma’s eye wall before the storm veered north. The different approach also means that Puerto Rico and other islands that suffered only glancing blows from Irma could now be directly confronted with hurricane conditions.

On Monday morning, Puerto Rico’s emergency officials were meeting to plan their response to Maria.

“The government is prepared,” Gov. Ricardo Rosselló said via Facebook, “and we ask of the citizenship preparation, attention, and action.”

Once it becomes a major hurricane, Maria is expected to remain one through the weekend.

As of Monday morning, Maria had maximum sustained winds of 90 mph and was heading west-northwest at 13 mph, the hurricane center said. On the Saffir-Simpson wind scale, a major hurricane designates Category 3 storms and higher — hurricanes with sustained winds of at least 111 mph.

Maria doesn’t have the historic size and strength of Irma. Its hurricane-force winds extend outward up to 15 miles — far short of the 70 miles such winds extended from Irma’s center.

Here are the conditions the National Hurricane Center warns could be brought by a Category 3 storm:

“Well-built framed homes may incur major damage or removal of roof decking and gable ends. Many trees will be snapped or uprooted, blocking numerous roads. Electricity and water will be unavailable for several days to weeks after the storm passes.”

Hurricane Jose, which buzzed the Leeward Islands as it moved north and west in Irma’s wake last week, has now weakened, with maximum sustained winds of 85 mph. Jose is currently about 280 miles east-southeast of Cape Hatteras, N.C., and it’s expected to remain off of the East Coast.

With Jose moving north at 9 mph, a tropical storm watch is in effect for areas from Fenwick Island to Sandy Hook; Delaware Bay South; East Rockaway Inlet to Plymouth; Block Island; Martha’s Vineyard; and Nantucket.